1. Field of the Invention
This invention relates to communication systems, methods and programs, and more particularly to use of a vocabulary formed using telephone keypad symbols to allow non-spoken communication by telephone.
2. Description of the Related Art
The following descriptions and examples are not admitted to be prior art by virtue of their inclusion within this section.
Communication by telephone has permeated business and social interaction to the point that a telephone is widely considered a necessity. Spoken communication by telephone is generally found to be natural and convenient by users. In some situations, however, spoken communication may be inconvenient or even impossible. For example, hearing-impaired people are generally unable to participate in conventional spoken telephone conversations. Those who have difficulty speaking or are unable to speak (as a result, for example, of congenital problems, illness or injury) have similar problems with telephone usage. Telephone users without hearing or speech impairments may also encounter difficulty with spoken communication in certain circumstances. For example, when a telephone user is located in a very loud environment (such as, e.g., a train station), both participants in the conversation may have difficulty hearing the conversation over the surrounding noise. In other environments, such as during artistic performances, the sound of a person talking on a telephone creates an undesirable distraction for others.
Efforts to enable telephone usage for hearing or speech-impaired persons have long been underway. An older approach which is still relatively common is the use of a teletypewriter, or TTY device. Such a TTY device, also known as a xe2x80x9ctelecommunication device for the deafxe2x80x9d, or TDD, is connected to the telephone of the hearing-impaired person, who communicates by typing onto a keyboard associated with the TDD and reading messages from an associated display. A TDD device must also be used by the person communicating with the hearing-impaired person. If a telephone with a TDD device is not available, a call can be completed by using a TDD relay service. For example, a conventional telephone user may call a TDD relay service, whereupon an operator uses a TDD to contact the TDD of the hearing-impaired person. Use of a human operator in such a relay service is known as xe2x80x9cvoice carry-overxe2x80x9d (VCO). Similarly, a hearing-impaired person may use a TDD to call a telephone number advertised by, for example, a business or government agency to reach a TDD relay service which then contacts the business by conventional telephone.
Use of VCO requires including a third person (the relay operator) in every telephone conversation, thereby compromising the privacy of the conversation. A system which allows TDD communication with an automated interactive menu system (such as may be used by, e.g., financial institutions or airlines in order to supply customer information without employing a human representative) has been disclosed in U.S. Pat. No. 5,121,421 to Alheim. This system includes a means for sending the menu prompts used by the interactive menu system to the TDD device of the hearing-impaired person for display, and receiving signals transmitted by the hearing-impaired person in response to the menu prompts, so that a human relay operator is not needed.
TDD devices transmit characters across a telephone line using coded tone signals. One such code is called Baudot, and ASCII coding may also be used. Other approaches to telephone communication for hearing-impaired users involve transmission of the dual-tone-multi-frequency (DTMF) tones used by a xe2x80x9ctouch-tonexe2x80x9d telephone. The set of DTMF signals typically used in telephone communications includes 12 tones, each tone a sum of tones of two frequencies. One of these two frequencies is from a group of four low-frequency tones, having frequencies form 697 Hz to 941 Hz. Each low-frequency tone is associated with one of the four rows of keys within a touch-tone telephone keypad. The other component of each DTMF tone has a frequency from a group of three high-frequency tones, ranging in frequency from 1209 Hz to 1477 Hz. Each high-frequency tone is associated with one of the three columns in the keypad. Pressing a key results in a specific combination of the corresponding row and column frequencies to produce the tone specific to that key.
In an article by Kraft in Circuit Cellar INK(copyright), October 1997, p. 18, a DTMF message decoder and display for use with the telephone of a hearing-impaired person is described. The decoder detects incoming sequences of DTMF tones sent by a standard touch-tone telephone in communication with the telephone of the hearing-impaired person, and displays an alphanumeric character corresponding to each tone sequence on the display so that a message may be read by the hearing-impaired person. Messages are sent to the decoder one letter at a time using a scheme in which multiple key presses are used to distinguish between the different letters associated with each key on the telephone keypad. For example, two presses of the xe2x80x9c2xe2x80x9d key in rapid succession are interpreted as the letter xe2x80x9cBxe2x80x9d. Another system for converting DTMF tones to alphanumeric characters in a message display for a hearing-impaired telephone user is disclosed in U.S. Pat. No. 4,426,555 to Underkoffler. In this system, the numerals one through nine are each sent by pressing the corresponding key on the telephone keypad once, while other characters such as letters and punctuation marks are sent using two-key sequences.
The above-described systems which display messages formed from characters sent using DTMF codes each require multiple key presses to be used to form most characters, a requirement which may make communication excessively time-consuming, tedious, and prone to error. A different approach to a DTMF decoding system, described in a paper by Shennib and Kondraske in Frontiers of Engineering and Computing in Health Carexe2x80x941984: Proceedingsxe2x80x94Sixth Annual Conference, IEEE Engineering in Medicine and Biology Society, allows transmission of words using a single keystroke for each letter of a word. A word is entered into the sending telephone by pressing in sequence the keys corresponding to the letters of the word, so that a numeric code is entered. The most likely word corresponding to the particular numeric code entered is then determined using an algorithm which compares portions of the numeric code to stored data including commonly-used syllables and corresponding numeric codes.
Although the system of Shennib and Kondraske allows a character in a message to be transmitted with a single keystroke rather than multiple keystrokes, all of the above-described approaches require sending messages one character at a time, making communication relatively slow. It would therefore be desirable to develop a system and method to allow more rapid non-spoken communication by telephone.
The problems outlined above are in large part addressed by a system and method for assigning a short code to each of a set of message units stored in memory within a code-compatible telephone. The message units may be alphanumeric or non-alphanumeric. An alphanumeric information unit preferably includes multiple alphanumeric characters, and may include a word, phrase, or message. For example, a code may be assigned to a particular written message, which may contain one or more sentences. Circuitry and/or software in the telephone is adapted to detect such an incoming code and display the corresponding message on the telephone""s display screen. Codes corresponding to phrases or words may also be sent sequentially to create messages, so that a message unit may comprise part of a message. A non-alphanumeric message unit may be a unit of graphic information, such as an icon or image. This graphic information is also forwarded to the telephone""s display screen if the corresponding code is received by the telephone. Alternatively, a non-alphanumeric message unit may contain auditory information, or information to be experienced through hearing. If a code corresponding to an auditory message unit is received, the message unit is forwarded to the telephone""s loudspeaker. The alphanumeric and non-alphanumeric message units may be generally referred to herein as xe2x80x9cmessage unitsxe2x80x9d or xe2x80x9cmessage informationxe2x80x9d.
After a connection is established between two telephones, the codes corresponding to the message units may be generated by pressing one or more keys on the transmitting telephone""s keypad. For example, the code xe2x80x9c78xe2x80x9d is generated at the transmitting telephone by pressing the xe2x80x9c7xe2x80x9d and xe2x80x9c8xe2x80x9d keys sequentially within a programmable time interval (if a longer time interval passes between pressing the two keys, they may be interpreted as separate xe2x80x9c7xe2x80x9d and xe2x80x9c8xe2x80x9d codes). If this code corresponds to an alphanumeric message, a corresponding word, phrase, or message (such as, e.g., xe2x80x9cYesxe2x80x9d or xe2x80x9cCould you repeat that please?xe2x80x9d) is shown on the receiving telephone""s display screen when the code is detected. In a currently preferred embodiment, the transmitting telephone sends DTMF tones when its keypad keys are pressed. The telephone may also send digital signals which are convertible to DTMF tones, however, or other signals capable of being converted to a form detectable by the receiving telephone.
In some embodiments, the transmitting telephone may be configured to store entered codes in a buffer and write them to a display screen on the transmitting telephone, independent of, or without, transmitting a code or codes until instructed to do so by the operator of the transmitting telephone. In such an embodiment, the user of the transmitting telephone may view and/or correct messages before transmission to the receiving telephone. In further embodiments, codes may be entered into the transmitting telephone by selecting a code from a list of codes and corresponding message units which is stored in the telephone.
In one embodiment, the system described herein may be used for non-spoken communication in one direction only. Such an embodiment could be used for communication between a hearing person and a hearing-impaired person who is not speech-impaired. The hearing person enters codes using a telephone keypad, and the corresponding message appears on the display screen of the hearing-impaired person""s telephone. The hearing-impaired person speaks to the hearing person in reply, at which time the hearing person may send an additional code, and the conversation continues in this manner. This one-way non-spoken communication mode may also be useful for situations in which only one of the persons involved in a telephone conversation is in an environment in which speaking into a telephone would distract others. The telephone from which the codes are transmitted in this mode may be a conventional telephone; i.e., this telephone does not need to have a display or be specially configured in order to participate in the communication.
In another mode of using the system, both telephones involved in a conversation are used for non-spoken communication. In this mode, each person inputs codes into a telephone, and views information on a display corresponding to codes sent by the other person. This mode may be useful for communication with a person who is both hearing-impaired and speech-impaired, or for communication between two hearing-impaired people. Two-way non-spoken communication could further be advantageous when at least one of the telephones involved is in a very noisy environment, making spoken speech difficult to distinguish, or when each telephone is in an environment in which speaking would distract others. In the two-way non-spoken communication mode, both telephones preferably include a display and are configured to detect codes sent from the other telephone and transfer the corresponding alphanumeric or graphical information to the display. In some embodiments of either the one-way or two-way non-spoken communication modes, a telephone used to transmit codes may be part of an automated interactive menu system.
As noted above, the system and method described herein allow either one-way or two-way non-spoken communication, which is believed to be advantageous for hearing-and/or speech-impaired telephone users, and for other persons in circumstances for which spoken communication is difficult or undesirable. As compared to the systems described in the xe2x80x9cDescription of the Related Artxe2x80x9d, the system described herein is believed to provide much faster communication, in that an entire message may be represented by a one- or two-digit code. For example, a two-digit code, entered using two keystrokes on a telephone keypad, could correspond to xe2x80x9cI""ll call you again tomorrowxe2x80x9d. When using the systems described in the previous section, on the other hand, this message would take at least 28 keystrokes (the number of characters, including spaces). The system described herein therefore results in much faster message entry. Furthermore, the communications system bandwidth used by a two-digit code representing a message is much smaller than that used by a sequence of codes in which at least one code is needed for each character of the message. Many more conversations can therefore be accommodated by a given communications link.
In an embodiment of the system, some of the codes sent by a transmitting telephone could correspond to auditory signals rather than information intended for visual display. Detection by the receiving telephone of a code corresponding to an auditory signal would result in the auditory signal being sent to the telephone""s speaker, rather than to the telephone""s display. Transmitting codes corresponding to auditory signals could be advantageous, for example, for a situation in which the transmitting telephone is in an environment for which non-spoken communication is preferred, and the receiving phone is being used by a person unable to read (e.g., a young child). In some embodiments for which auditory message units are used, an image or message is simultaneously forwarded to a display screen associated with the receiving telephone. Such a display would alert a person looking at the display that an auditory message was being sent. This may be useful, for example, in lessening confusion in situations in which an auditory message is inadvertently sent to the code-compatible telephone of a hearing-impaired person. The image or message could also be forwarded to the display screen just before the auditory message is forwarded to the speaker. In this way, a hearing person using a code-compatible telephone having a display screen in the handset would be alerted to move the telephone to put the speaker near the ear and listen to the auditory message. Since telephones having the display screen in the handset do not allow simultaneous viewing of the screen and listening to the speaker, loss of information may be avoided by such an alert.
The receiving of codes corresponding to message information may be implemented using a xe2x80x9ccode-compatiblexe2x80x9d telephone including a display, a processor, and memory, in which correspondence data relating codes to message units is stored in the memory, and the processor executes instructions operable to detect incoming codes and forward the corresponding message units to the display (or speaker, in the case of auditory message information). Telephones including a display, processor and memory are currently commercially available and becoming increasingly common, as telephones incorporate increasingly more sophisticated features such as caller identification and directory storage applications. The code-compatible telephone may be configured to communicate over either a cable (also called xe2x80x9cland linexe2x80x9d or xe2x80x9cwirelinexe2x80x9d) or wireless link.
The correspondence data and program instructions described above may be programmed into the telephone at the time of manufacture to form the code-compatible telephone, or downloaded to the telephone using a cable or wireless link. The downloaded data may come from another telephone, or from another device such as a computer. In some embodiments, the correspondence data relating particular codes to message units may be added to or updated by downloading, so that the available message unit options may be customized for particular types of conversation. For example, a different set of message options may be most useful for conversation with a relative than with, for example, a financial institution. In some embodiments, a one-way or two-way transfer of correspondence data may be performed at the beginning of a telephone conversation, to ensure that the most useful messages are available for that conversation. In particular, correspondence data may be transferred from one telephone to a code-compatible telephone independent of, or without (absence of), any action being taken by the operator of the code-compatible telephone. Such a transfer allows very specific messages to be sent to and correctly interpreted by the code-compatible telephone. In another embodiment, a telephone could receive downloaded data from a third party source, as opposed to another telephone to be communicated with. In such an embodiment, a telephone number could be dialed to establish a connection with the third party server (e.g. computer or telephone), and specific data could be downloaded from the server. Such third party servers might offer correspondence data sets for communication regarding specialized topics not generally included in code-compatible telephones as manufactured.
In addition to the code-compatible telephone and methods for its use described above, a method for processing input to a telephone is contemplated herein. A code generated in response to the pressing of one or more keys or selection of a stored code on a transmitting telephone is detected. The message unit corresponding to the detected code is identified, and in the case of verbal or graphical information, is forwarded to the display of the code-compatible telephone. If the message unit is auditory, it is forwarded to the speaker of the telephone. The method may include determining whether input to the telephone constitutes message codes or conventional voice input. The method may also include receiving and/or transmitting correspondence data relating codes to message units.
A computer-usable carrier medium having correspondence data as described above and/or program instructions executable to implement the above-described method for processing input is also contemplated herein. The carrier medium may be a storage medium, such as a magnetic or optical disk, a magnetic tape, or a memory. In addition, the carrier medium may be a wire, cable, or wireless medium along which the program instructions are transmitted, or a signal carrying the program instructions along such a wire, cable or wireless medium. In an embodiment, the carrier medium may contain program instructions executable to implement detection of a code generated in response to pressing one or more telephone keypad keys, identification of the message unit corresponding to the code, and forwarding of the message unit to a display. In some embodiments, the carrier medium further includes instructions executable to forward an auditory message corresponding to a detected code to a speaker. The carrier medium may alternatively contain correspondence data as described above, or may contain both correspondence data and program instructions.